Silencing of ste14, Rab7, and Rab8 reduces Notch signaling in D. melanogaster wings. (A) Adult wing of Ap-Gal4; UAS-Dcr2 flies expressing the indicated GAL4-responsive UAS-shRNAs and UAS transgenes at 29°C. Expression of UAS-fng or UAS-Su(H) but not UAS-Su(dx) rescued the wing vein Delta phenotype (arrows) observed in the L4 and L5 veins of the wings expressing UAS-ste14 shRNA, UAS-Rab7 shRNA, or UAS-Rab8 shRNA. Below the representative wings, the widths of the bifurcation of L4 and L5 are plotted as percentages of the wing width. Data shown are means ± SEM. n = 10. *, P < 0.05 (two-sided t test). NA, not assessable because the majority of wings were crumpled and vein width could not be measured accurately. (B) Adult wing of Ap-Gal4; UAS-Dcr2 flies expressing the indicated GAL4-responsive UAS-shRNAs at 25°C. Bar, 1 mm. Knockdown of ste14, Rab7, or Rab8 enhanced the notched wing phenotype observed with knockdown of Serrate (Ser).